The Cabinet Office has confirmed ministers intend to press on with reform of the CSCS despite the setback in the High Court.

The changes initially imposed by the government from April 2010 meant Whitehall redundancy packages were capped at a maximum of two years’ salary for employees earning £25,000 or more – civil servants who had worked 20 years at Whitehall were previously entitled to three years’ pay. Those who rejoined the Civil Service after receiving a severance payment were also forced to pay some of the money back.

A spokesman said: “As outlined in the coalition agreement, we are looking at ways to reform the CSCS to bring it more into line with good practice in the private sector.

“Our intention would always be to seek to reach a negotiated agreement, which would include protection for lower-paid civil servants.”

If agreement on reform cannot be reached, ministers could have to amend the 1972 Superannuation Act, which established the redundancy rules.

But it is understood that HR directors in Whitehall have already received letters telling them they shouldn’t assume the status quo will last for more than the next couple of months, which suggests change could be forced through, the BBC has reported.